1. Field of the Invention
The present invention relates to a headlamp, and more particularly to a headlamp comprising an aiming adjustment device which is provided with an adjustment prevention mechanism to prevent any change of the aiming adjustment of the headlamp completed during a manufacturing process after shipment from the manufacturer.
2. Background Art
FIG. 3 shows a conventional headlamp 90. Since a manufacturing error is inevitable on the headlamp 90 and an automotive body 30 after the headlamp 90 is manufactured, some adjustments are required after the headlamp 90 is mounted on the automotive body 30 so that a specified beam direction should be obtained.
Accordingly, the headlamp 90 is equipped with an aiming adjustment device 91 that, for example, enables a reflector to be adjusted vertically and horizontally. An adjusting element 91a of said aiming adjustment device 91 is for example extended from an external surface of a housing 90a of the headlamp 90 for an adjustment purpose after the headlamp 90 is mounted on the automotive vehicle. Thus, the headlamp 90 can be easily adjusted from the outside after the headlamp 90 is mounted on the automotive vehicle.
However, if the adjusting element 91a is extended to the external surface of the housing 90a and is exposed as mentioned above, even a user of the automotive vehicle is capable of adjustment, leaving possibilities of improper adjustment by users who do not have the full and accurate knowledge about aiming. Depending on destination countries, the standard specifies provision of the adjustment prevention mechanism 92 to prevent users from manipulating the adjusting element 91a.
The conventional adjustment prevention mechanism 92 consists of a cover 92a for covering said adjusting element 91a and a mounting screw 92b (or a rivet depending on cases) for fixing the cover 92a on the housing 90a. After completion of the aiming adjustment, the manufacturer mounts the cover 92a with the mounting screw 92b to prevent any adjustment thereafter.
When the headlamp 90 is mounted on an actual automotive body 30, however, almost no gap is left between the housing 90a and the automotive body 30 in most cases as shown in FIG. 3. After completion of the aiming adjustment, there hardly remains a workspace for mounting said cover 92a of the adjustment prevention mechanism 92 and fixing the mounting screw 92b. Thus, this work is very hard to perform and takes a great deal of time, therefore raises problems such as decreased productivity and high cost.